Novel method for producing 9beta, 10alpha-6-methylene testosterone



United States Patent 3,414,591 NOVEL METHOD FOR PRODUCING 9fl,10oc-6- METHYLENE TESTOSTERONE Harmeu van Kamp, Van Houtenlaan, Weesp, Netherlands, assignor to North American Philips Company, Inc., New York, N .Y., a corporation of Delaware No Drawing. Filed July 9, 1965, Ser. No. 470,913 Claims priority, application Great Britain, Apr. 9, 1965, 15,186/ 65 1 Claim. (Cl. 260-397.4)

ABSTRACT OF THE DISCLOSURE Produce 3 keto 4 dehydro 6 trihalomethyl 913,100: steroid of the androstane series by treating corresponding 3-hydrogen compound with enolalkylating compound and then with trihalomethane without separation of the 3- enolether intermediate. Further the resultant 3-keto-4- dehydro-6-trihalomethyl 913,1000 steroid is converted to the corresponding 6 methylene compound by treatment with chromous chloride in the presence of hydrochloric acid. This abstract is not intended to be a description of the invention defined by the claims.

My invention relates to a novel method of producing 3-keto-4-dehydro-6-trihalogenomethyl 9,8,10a steroids and to a method of converting the latter group of steroids into the corresponding 6-methylene-9/3,10a-steroids. 3- keto-4-dehydro-6-trichloromethyl and the corresponding 6-tI'lbIOmOlTlCthy1-9B,IOOL-StCl'OidS having at carbon atom 17 a hydroxyl-, acyloxyor alkoxy group in fl-position and at this carbon atom in tat-position a hydrogen atom or a methyl, vinyl, an ethyl or an ethynyl group form the subject matter of copending application U.S. Ser. No. 470,871, filed July 9, 1965 now abandoned of which I am co-inventor.

The underlying invention relates to a novel method of producing these 6-trichloroor 6-tribromo-methyl 9B, IDOL-steroids. This novel method has the advantage of giving relatively high yields of the desired end-product. Another advantage of this process is that it can be carried out rather easily and that no isolation of intermediately formed intermediates is necessary.

The invention consists in a method of producing a compound of the formula CH OR17 in which formula CX represents a trichloromethyl or a tribromomethyl group 0R is hydroxy ;or an acyloxy or alkoxy group and R' is a hydrogen atom or a methyl, an ethyl, a vinyl or an ethynyl group,

Patented Dec. 3, 1968 ice by reacting a compound of the formula CH 0 Ha in which Formula OR and R' have the aforesaid meaning with an enolalkylating agent to produce a 3- alkoxy 3,5-bisdehydro-9fl,10a-steroid, which compound Without intermediate purification or isolation is reacted with tetrabromomethane or trichloromonobromomethane in the presence of a tertiary amine and, if desired in the presence of reaction catalysts.

A suitable enolalkylating agent is for example an alkylorthoformate in a medium of dioxan or benzene to which medium catalytic amounts of ,B-toluene sulphonic acid have been added. As alkylortho formate use may be made of ethylorthoformate. Tertiary amines, which are used to bind hydrobromic acid as formed during the reaction between the enolether and tetrabromomethane or trichloromonobromomethane, are for example pyridine, collidine, or N,N-diethyl (or -dimethyl)-aniline.

As a reaction catalyst use may be made of peroxides e.g. benzoyl peroxide. Further it is of advantage to have the introduction of a trichloromethyl group taken place in the presence of light such as direct sunlight. Another part of my invention consists in converting 6-tribromo (or trichloro)-methyl-9B,10x-steroids as aforesaid into the corresponding 6-methylene compounds, which compounds form part of the subject matter of application U.S. Ser. No. 470,894 filed July 9, 1965 now abandoned of which I am co-inventor. 6-methylene-steroids may be prepared according to the so-called Vilsmeyer reaction.

According to this reaction a 3-alkoxy-3,S-diene-steroid is reacted with 'dimethylformamide and phosgene. After hydrolysis of an intermediately produced iminium compound the corresponding 6-formal-3-alkoxy-3,5-diene is produced.

By catalytic reduction or by reduction with sodiumor lithium borohydri-de the corresponding 6-hydroxymethyl-3-alkoXy-3,5-diene is obtained. Subsequent treatment of the latter compound with aqueous diluted acid results into hydrolysis of the enolether groupand simultaneously of dehydration of the 6-hydroxymethyl group. Preferably this reaction is carried out in a medium of aqueous diluted acetic acid or hydrochloric or sulphuric acid in a medium of a lower alkanol, e.g. methanol.

1 have found that introduction of a 6-methylene group may be carried out in a more simple way by reacting a ,6-trihalomethyl-9B,l0a-steroid with chromous chloride in the presence of hydrochloric acid. This reaction gives high yields of the desired 3-kct0-4-dehydr0-6-methylene- 95,10a-ster0ids. Such compounds are disclosed in United States application Ser. No. 470,894, filed July 7, 1965 of which I am a co-inventor.,

This part of my invention consists in a method of producing 3-keto-4-dehydro-6-methylene-9fl,loot-steroids which reaction is characterized by reacting a compound of the formula in which formula A suitable medium for carrying out the reaction consists of a mixture of ethanol and tetrahydrofuron.

The hydrogen atoms or methyl groups at the carbon atoms 8, 9, 10, 13 and 14 of the steroids used in my inventive processes have the same stereo chemical configurations as the corresponding hydrogen atoms and methyl groups in dihydroiso-lumisterone. Castells et al, Proc. of the Chemical Soc. Jan., 1958, p. 7, have shown that dihydroisoluministerone has the configuration 85, 9,6, IOa-methyl, ISB-methyl, 140:.

The expression 95,10 is used in this application to indicate at which carbon atoms (9 and the stereochemical configuration deviates from the one of the normal steroids and in which sense (9,8,1066 in contra distinction to the 9:1, lOB-configuration of the normal steroids.

In this application the ,B-configuration of a hydrogen atom, a methyl group or of an other substituent not bound to a unsaturated carbon atom is indicated by a solid line. A dotted line represents the a-configuration. The expressions alkoxy and acyloxy used in this application have the following meaning: Alkoxy alkoxy group con taining 1-10 carbon atoms. The alkyl part of the alkoxy group is preferably an aliphatic, alicyclic, mixed aliphaticaromatic or mixed aliphatic-alicyclic group. Examples of alkoxy are: methoxy-, ethoxy-, propoxy-, tert-but0xy-, cyclopentyloxy-, cyclohexyloxy and benzyloxy, methylcyclopentyloxy;

Acyloxy: acyloxy group containing from 1-20 carbon atoms. The acyl part of the acyloxy group is preferably the acyl group of saturated or unsaturated aliphatic mono-, dior tricarboxylic acid, mixed aliphatic-aromatic carboxylic acid, aromatic carboxylic acid, saturated or unsaturated or alicyclicor mixed aliphaticalicyclic monocarboxylic acid, especially those having from 1-6 carbon atoms. Examples of acyloxy groups are: formoxy-, acet0xy-, propionoxy-, butyroxy-, acyloxy groups of oleic acid, palmitic acid, stearic acid, enanthocic acid, undecyloic acid, caproic acid, pivalic acid, succinic acid, malonic acid, citric acid, benzoic acid and p-hexyloxyphenyl propionic acid, hexahydrobenzoic acid, phenylacetic acid, B-cyclopentylpropionic acid, fl-cyclohexylpropionic acid.

Example 1.6 8-tribromomethyl-17 3-hydroxy-9fi,10aandrost-4-en-3-one 17-acetate To a solution of 6 g. of 17fi-hydoxy-9B,10ot-androst-4- en-3-one 17-acetate in 75 ml. of dry, freshly distilled dioxan, 4.1 m1. of ethyl orthoformate and 100 mg. of ptoluenesulfonic were added. The mixture was allowed to stand in a well-closed vessel at room temperature for 48 hours, in which time the enoletherification was mostly completed. The conversion into the 3-enol-ether was checked by means of thin-layer chromatography (benzene+2% of acetone+-0.1% of pyridine). In the case the conversion was not nearly complete, the mixture was after the addition of 1.5 ml. of ethyl orthoformate, kept at room temperature for an additional period of 24 hours. To the solution were then added 2.9 ml. of pyridine and 18.1 g. of tetrabromomethane. The mixture was allowed to stand in difiuse daylight at room temperature for 10 days. The crystalline precipitate was filtered oil? and the filtrate was after dilution with methylene chloride, washed with Water, 2 N sulfuric acid, water, 5%, sodium bicarbonate solution and finally with water. After drying and evaporation of the solvents, the residue was triturated with ether, to give 7.2 g. of 6/3-tribromomethyl-17p-hydroxy- 9 3,l0a-androst-4-en-3-one 17 acetate. An analytical sample was obtained by chromatography on silicagel (elution with methylene chloride), M.P. 180 (Kofier); [u] 68.5; e240 Nm.=13 700; LR. 725, 742, 871, 877, 1031, 1048, 1253, 1374, 1612, 1674 and 1730 cmr N.M.R. O.87/s.(3) CH -18; 1.38/s.(3) CH -19; 2.03/s. (3) CH -Ac; 3.36/dm./J=11 c./s.(1) CH-6; 4.70/m.(1) CH-17; 5.27/s. CH Cl 6.38/d./J=1 c./s.(1) CH-4.

Example 2.6;3trichloromethyl-17fi-hydroxy-9B,10aandrost-4-en-3-one 17-acetate 6fl-t-richloromethyl-9p,10a-pregn-4-ene-3,20-dione From 9B,10a-pregn-4-ene-3,20-dione, yield 50%; M.P.

2055-2065"; [a] =37.5; e238 Nm.=13,900; LR. 776, 787, 86 8, 878, 1363, 1617, 1679 and 1701 GEL Example 3 .6-methy1ene-17B-hydroxy-9fi,10a-androst- 4-en-3-one 17-acetate A solution of 3.7 g. of 6B-trichloromethyl-17p-hydroxy- 9,3,10m-androst-4-en-3-one 17-acetate prepared as described in Example 2 in ml. of tetrahydrofuran was treated at room temperature with a chromous chloride solution (prepared from 24 g. of chromic chloride in 175 ml. of ethanol and 35 ml. of cone. hydrochloric acid, and 20 g. of zinc) in a nitrogen atmosphere. The mixture was stirred for 40 min., poured into Water and extracted with methylene chloride. The extract was washed with water, a 5% sodium bicarbonate solution and water. After drying and evaporation of the solvents, the residue was chromatographed on silicagel to yield after recrystallization from ether 1.71 g. of 6-methylene-17;8-hydroxy-9}3, 10a-androst-4-en-3-one 17-acetate with M.P. -141; e255 Nm.=9,780; LR. 871, 875, 905, 1025, 1042, 1247, 1605, 1630 (sh.), 1670, 1740, 1815, 3030 and 3080 cm. N.M.R. 0.88/s.(3 CH 18; 1.27/s.(3) CH 19; 2.04/s. (3) CH Ac; 4.67/m.(1) CH-17; 4.91/d.(1), 5.04/d. (1)=CH 6; 5.83/s.(1) (DH-4.

Example 4 .-6 ,B-trichloromethyl- 17 B-hydroxy-l 7-methyl- 9 8,10a-androst-4-en-3-one 17-acetate l7fl-hydroxy-9B,10a-androst-4-en-3-one was converted into a corresponding 3 enamino-3,5-bisdehydro-9fi,10asteroid. This compound was oxidized to produce 3-en amino-9 3,10a-androsta-3,5-dien-17-one which latter compound was reacted with methyl-magnesiumbromide which reaction after hydrolysis resulted in formation of 17- methyl-l7/3-hydroxy-9B,10a-androst-4-en-3-one. This compound was esterified with acetylchloride and some pyridine to produce the corresponding 17-acetate.

The 17-acetate was converted into fi-trichloromethyl- 17fl-hydroxy-17-9/3,10m-androst-4-en-3-one 17-acetate by the method described in Example 1 using however tetra- 5 chloromethane instead of tetrabromornethane. M.P. 1885-1895"; s 238.5 Nm.=14,350; [11],; =99. LR. 657, 683, 780, 879,.1016, 1037, 1268, 1410, 1610, 1675 and 1725 cmr N.M.R. 0.95/s. (3) CH 18; 1.40/s. (3) CH --19; 1.51/s. (3) CH -17; 198/s. (3)

3.37/dm./J=12 c./s. (1) CH6; 6.31/d./I:1 c./s. (1) CH4.

What is claimed is:

1. A method of producing 3-keto-4-dehydro-6 methylene-9 3,10u-steroids comprising reacting a compound of the formula References Cited UNITED STATES PATENTS 8/1965 Reerink et a1 260239.55 3/1961 Godtfredsen 260397.4

ELBERT L. ROBERTS, Priman Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,414,591 December 3, 1968 Harmen van Kamp It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below: Column 4, line 57, s.(3q" should read 5(3) line 74, "l79B,10cx" should read 17-methy1-9B, 10a

Signed and sealed this 7th day of April 1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer 

